Analysis And Experiments Of A Rough Wall Climbing Robot Based On Grabbing Claws

Climbing robot is one of the special robots work in extreme environment,applied to military reconnaissance and aerial work.Most previous climbing robot are generally developed using adhesives,suction cups,magnets and micro-hooks.However,cable-stayed bridge towers and viaduct piers in remote mountain are under vibration state for a long time because of the influence of high-altitude wind load and the external environment.Traditional climbing robots which use suction,magnetic adhesion and dry adhesion are not capable of climbing on these rough surfaces.Micro-hooks can be effective,however,when the rough surface vibrate there will be no generation of an attachment force and easy to be affected by outer.Based on the analysis of the interaction mechanism between the hook and rough wall,this paper proposes a three-dimensional rough wall graspable position discrimination algorithm,which provides a theoretical basis for the design of the hook size.Inspired by the beetle claws,this paper introduces a Cross-shaped claw grasp module,through theoretical analysis and finite element analysis point out the advantages and reliability of this design.Finally,through experiments verified the performance and anti-disturbance ability of the Cross-shaped claw.The main innovations are as follows:1.An experimental measurement rough wall was made and used three-dimensional scanner to get the rough wall surface point cloud data.Then,the three-dimensional contour and two-dimensional contour of the wall were simulated respectively.Based on the wall simulation,this paper summarized the idealized models of several asperities,analyzed the mechanism of the micro hooks with the idealized model.Finally,the relationship between the hook size and the wall roughness parameters is established.2.Based on the study of the interaction between the cross section of the 2D hook and the profile of the rough wall.This paper proposes a three-dimensional rough wall graspable position discrimination algorithm.By using the triangle segmentation strategy proposed in this paper,the cloud is divided into a certain area to determine whether each region satisfies the graspable condition.The experimental and simulation results show that the algorithm has the feasibility and certain practical value,which provides a theoretical basis for further study of the real rough wall graspable position.3.Using Solidworks designed a Cross-shaped claw grasp module,which can take "hook" and "grasp" two ways attached to the rough wall.Combined with the action mechanism of the hook wtih the rough wall and the simulation results of the three-dimensional rough wall graspable position judgment algorithm,the terminal hook was designed.The rationality and reliability of the mechanism are verified by simulation analysis and finite element analysis respectively.Finally,an optimal direction is proposed for the design of the claw gripping module by modal analysis.4.Developed a prototype of Cross-shaped claw grasp module and relevant grasp experiment was carried out,especially the preliminary experiment was carried out under the vibration state.The experimental results show that the Cross-shaped claw grasp module can achieve stable on the static wall,and also has good grasp performance on the vibration wall.Cross-shaped claw grasp module have some anti-vibration,anti-tipping and anti-reversing ability,which provides a basis for the design and research of rough wall climbing robot under the condition of vibration.